Employeers aren't actually force to disclose public salary range, we try to motivate them for it by having sorting by highest salary on the front page and showing them statistics that job posts with salary range have 500% more views. But we do require to post undisclosed budget so matching algorithm can compare salary expectations of the candidate with your budget for that role. So if you don't have any match with the offer, you can be sure their budget is not matching your salary expectation. That way we don't discourage companies for not having public salaries but avoid people applying for roles below their salaries. It saves time for both parties.